Many organizations support the colonization of Mars. They have also given different reasons and ways humans can live on Mars. One of the oldest organizations is the Mars Society. They promote a NASA program that supports human colonies on Mars. The Mars Society have set up Mars analog research stations in Canada and the United States. All other organizations include MarsDrive, who wants to help fund settlements on Mars, and Mars to Stay. Mars to Stay advocates settlements on Mars. In June 2012, Mars One released a statement that they believe could help start a colony on Mars by 2023.

Mars has a surface area that is 28.4% of Earth's. It is slightly less than the amount of dry land on Earth (which is 29.2% or Earth's surface). The radius of Mars is half that of Earth and only one-tenth the mass. This means that it has a smaller volume (~15%). Mars also has a lower average density than Earth.

Mars has an axial tilt of 25.19°. Earth's axial tilt is 23.44°. This means that Mars has seasons similar to Earth. However, seasons on Mars last twice as long because the Martian year is about 1.88 Earth years. Mars' north pole currently points at Cygnus and not Ursa Minor.

Conditions on the surface of Mars are much closer to habitability than the surface of any other known planets or moons. Other planets such as Mercury has extreme hot and cold temperatures. Venus is very hot and all other planets and moons are very cold. There are some natural places on Earth, where humans have explored, that is similar to the conditions on Mars. The highest altitude reached by a balloon that was carrying humans, was 34,668 meters (113,740 feet), a record set in May 1961.[3] The pressure at that altitude is about the same as on the surface of Mars.[4] Extreme cold in the Arctic and Antarctic match all but the most extreme temperatures on Mars.